/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * See the NOTICE file distributed with this work for additional
 * information regarding copyright ownership.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.appium.java_client.internal;

import com.google.common.collect.Collections2;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;

import io.appium.java_client.MobileElement;

import org.openqa.selenium.internal.WrapsElement;
import org.openqa.selenium.remote.RemoteWebElement;
import org.openqa.selenium.remote.internal.WebElementToJsonConverter;

import java.util.Collection;
import java.util.Map;

/**
 * Converts {@link RemoteWebElement} objects, which may be
 * {@link WrapsElement wrapped}, into their JSON representation as defined by
 * the WebDriver wire protocol. This class will recursively convert Lists and
 * Maps to catch nested references.
 */
public class MobileElementToJsonConverter extends WebElementToJsonConverter {

    /**
     * Converts {@link RemoteWebElement} objects, which may be
     * {@link WrapsElement wrapped}, into their JSON representation as defined by
     * the WebDriver wire protocol.
     *
     * @param arg is the argument
     * @return the result
     */
    public Object apply(Object arg) {
        if (arg == null
            || arg instanceof String
            || arg instanceof Boolean
            || arg instanceof Number) {
            return arg;
        }

        while (arg instanceof WrapsElement) {
            arg = ((WrapsElement) arg).getWrappedElement();
        }

        if (arg instanceof MobileElement) {
            return ImmutableMap.of("ELEMENT", ((MobileElement) arg).getId());
        }

        if (arg.getClass().isArray()) {
            arg = Lists.newArrayList((Object[]) arg);
        }

        if (arg instanceof Collection<?>) {
            Collection<?> args = (Collection<?>) arg;
            return Collections2.transform(args, this);
        }

        if (arg instanceof Map<?, ?>) {
            Map<?, ?> args = (Map<?, ?>) arg;
            Map<String, Object> converted = Maps.newHashMapWithExpectedSize(args.size());
            for (Map.Entry<?, ?> entry : args.entrySet()) {
                Object key = entry.getKey();
                if (!(key instanceof String)) {
                    throw new IllegalArgumentException(
                        "All keys in Map script arguments must be strings: " + key.getClass()
                            .getName());
                }
                converted.put((String) key, apply(entry.getValue()));
            }
            return converted;
        }

        throw new IllegalArgumentException(
            "Argument is of an illegal type: " + arg.getClass().getName());
    }
}
